U0621Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 1
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- U0621 mirrors U061F on bank 2: messages from the first exhaust temperature sensor of the second cylinder bank no longer reach the controller, so the code only appears on V engines or other layouts with two exhaust paths. Bentley documents it for the V8 in the Continental GT, GTC and Flying Spur, model years 2020 to 2023 (bulletins 2065698/1 and 2065698/2): the emission warning lamp is lit and the fault memory shows U0621, often alongside U061F, as intermittent or static. The cause was the sensor harness routed close to the subframe and worn through on a bracket inside the wheel-arch liner; the repair is mending the wires and re-securing them so they cannot touch nearby parts again. GM's SENT diesel tables contain no bank 2 code. Analog circuit faults at this position are P0547 to P0549.
- What you may notice
- Emission warning lamp on
- Code logged as intermittent first, later static
- Likely causes
- LikelyHarness rubbed through on the subframe or a wheel-arch bracket
- PossibleElectronics of the bank 2 sensor failed
- RareConnector not latched or corroded
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.